Specialized Aethos as a Race bike

Wanting some opinions from aethos owners. I currently own a Tarmac SL6 and am looking at buying an aethos expert to use as a race bike. Has anyone here thrown on some deep section wheels and raced an aethos? Race experiences, results, and just some general advice/opinions?


The geometry is basically the same as a SL6. You will probably not be able to notice a difference between the two bikes.


No it’s not allowed - Specialized heavies will come to your house and smash it with hammers if they find out. JK, if it’s good enough for Kasper Asgreen, it’s good enough for you :+1:


This is a bit of a silly question. It’ll be highly capable. You might give up 10w in the lab, but only 2w-5w aero watts in the real world (water bottles and wind turbulence, etc).

All the BS around the bike is because Spec had to justify it’s existence after going all aero. The Aethos is only lighter than the (more round) SL4/SL5/SL6 because they were able to reduce the safety factor in the design needed to account for the variables in the manufacturing process (robotic carbon tape laying, i think; elimination of ‘short tow’ unidirctional layers).

Anyways, it’s basically a Tarmac without the aero for people who like light things. It’ll ride better because there’s not as much material at the joints and the seatpost junction is effectively lower. Any bike on the market is going to be stiff enough to ride Roubaix (off road effectively) taking 6in jump with stiff aero wheels and a 260lb person on the bike. Since the geometry is the same as the Tarmac, you’re not going to see some odd leverage issue that you maybe might see on a long wheelbase/short stem/slack style gravel bike.


Didnt’ see that… thanks - guess I’m wrong about the mfg process and safety factor.

They re-weighted their tube sizes to be downtube and headtube fat (less aero), while demphasizing the BB size, with the secret being the tapering from the big tubes to the smaller ones.
In any case, the rest of realities are true and there’s no reason not to use the bike however you want.

Is there a reason you don’t want to use the Tarmac as a race bike?

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No real reason. Just looking at different race bike options for next year

I’d keep the SL6. The big benefit of the Aethos is its low weight, the more expensive model I think clocks in at 6 kg.

But if you want to race, that is all null and void, because you need to stick to the 6.8 kg weight limit. Even if the Aethos is lighter than your SL6, I don’t think it is worth it.


Unless you are racing at the highest levels the weight limit doesn’t matter… no one is weighing bikes.


I have never raced in the US, but here in Japan they do check bike weights (and gearing for juniors) in all JCBF sanctioned events. In the non-sanctioned events I have participated in, they haven’t. In the UK hill climb scene, they also don’t seem to adhere to the 6.8 kg weight limit either.

Fair point and not sure where the OP is. In general in the US they don’t weigh even in Cat 1. That being said, it depends where you are racing but I doubt that weight is the deciding factor in most races.


The thing is: even if they don’t check the weight (or whether you use performance-enhancing substances), I think the rules are quite clear nevertheless. And if the OP went for the much lighter 6 kg bike, it is not as if your bike weighs 6.7 kg and you just cut it a little too close. That’s deliberate. Just my two yen.

Probably all a moot point since I don’t think an expert trim with deep wheels is getting close to the limit.

There is no weight limit in the US under USAC unless racing a UCI race or national championship.


Who’s weighing bikes at your local neighborhood race scene?
ETA: I should read further before commenting

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If that is the case, then sure, you can disregard my comments. But IMHO you should know that for sure before buying such an expensive bike.

To be fair, the referees used their hand + experience for a first measurement, but I am quite certain they had a proper scale at hand. My old bike weighed 9 kg, so they did not have to double-check.

For the gearing they had markers on the ground and diligently checked how far the bike would go over one pedal revolution by pushing it backwards.

The most annoying rule was that your helmet needed a JCBF approved sticker that you only get when you buy your helmet domestically. I bought mine on Wiggle and the Japanese distributor refused to send me one, because I hadn’t bought it in Japan. Annoying. But the helmet is on the list of approved equipment and got a sticker from a buddy, so everything was above boards.


You can just go to a bike shop and buy a cheap helmet for winter, off-road riding, or commuting that hasn’t had the JCL sticker affixed yet and slap it on your road riding / racing / TT helmet.

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Did you make a decision here? So torn as I’ve seen so many contrasting opinions between the aethos being the best bike ever and vastly overrated… I have a sl7 but I want to keep it setup and prepped for racing and as it’s a special model wanted to keep it more for summer riding. All I’m interested in is racing up to like 100 miles and after a winter everyday training bike, just not sure whether to get another sl7 so I can mimic exact setups or try the aethos, just seen a lot about it being a bit overrated

Having never ridden either bike because $$&, I would definitely push you toward the aethos (or at least not another SL7). Not because it’s a better bike or anything but I see little benefit to having two of the same bike. The set ups don’t need to be exact but having two different bikes just gives you more options to mix it up.

Also, I would do your best to ride both. Don’t listen to reviews that say it’s overrated. Go ride one and find out for yourself.

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